31213201223 has 4 divisors (see below), whose sum is σ = 31218699288. Its totient is φ = 31207703160.

The previous prime is 31213201213. The next prime is 31213201301. The reversal of 31213201223 is 32210231213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32210231213 = 19 ⋅1695275327.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31213201223 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31213201195 and 31213201204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31213201213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2740508 + ... + 2751873.

It is an arithmetic number, because the mean of its divisors is an integer number (7804674822).

Almost surely, 2^31213201223 is an apocalyptic number.

31213201223 is a deficient number, since it is larger than the sum of its proper divisors (5498065).

31213201223 is an equidigital number, since it uses as much as digits as its factorization.

31213201223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5498064.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 31213201223 its reverse (32210231213), we get a palindrome (63423432436).

The spelling of 31213201223 in words is "thirty-one billion, two hundred thirteen million, two hundred one thousand, two hundred twenty-three".